This brochure explains the underlying disorders in respiratory mechanics in cases of COPD (Chronic Obstructive Pulmonary Disease) with emphysemic components and the difficulties those disorders present for spontaneous breathing and mechanical ventilation. It also covers therapeutic options developed to optimize ventilation treatment for affected patients. In the first section the reader should acquire a basic understanding of the pathophysiology of the clinical pictures of COPD and pulmonary emphysema and the effects on respiratory mechanics. The second section describes special ventilator functions specifically developed to overcome these constraints under mechanical ventilation.